1. Field Of The Invention
The present invention relates to a soldering apparatus in which a soldering wire is fed adjacent to the tip of a soldering iron and also relates to a hand-held soldering iron for use in such an apparatus.
2. Description Of The Prior Art
A conventional soldering apparatus is disclosed in U.S. Pat. No. 3,990,622. This soldering apparatus includes a soldering wire storage spool and a soldering wire feeding mechanism having a knurled feed wheel, which unwinds the soldering wire from the storage spool. The soldering wire is fed and guided through a hose-like tube to a metal tube which is mounted to the soldering iron. This metal tube extends to a location adjacent the soldering iron tip and directs the soldering wire onto the soldering iron tip. At its free end, i.e. the end section adjacent to the soldering iron tip, this metal tube has a curvilinear shape to guide the soldering wire along a curvilinear path onto the soldering iron tip.
As disclosed in U.S. Pat. No. 3,990,622, the driving or wire feeding mechanism, the hose-like tube and the metal tube are designed as a custom-made unit with each such unit fitting one commonly used diameter of soldering wire. It is, therefore, necessary to exchange the above described unit whenever a soldering wire having a different diameter is used, so that a large number of such units must be kept in stock. Also, the use of such a unit precludes decreasing the number of connecting lines by combining them, as, for example, by using one hose-like tube for several soldering wire diameters.
German DE-GM No. 78 31 576 discloses a soldering wire feeding mechanism of the kind described above which operates to transport a soldering wire through an electrical cable to a metal tube. A pathway through the cable may be formed by removing one electrical lead if the electrical cable has, for example, three leads. The metal tube is mounted at one end to the manual grip of the soldering iron and the opposite, free end is a curvilinearly extending section. To properly guide the soldering wire, the inner diameter of the metal tube must fit the outer diameter of a commonly used soldering wire, so that the use of a number of soldering wires having a variety of diameters is very limited. This is also true for the pathway through the above mentioned electrical cable. Due to the bent or curvilinearly extending end section of the metal tube, and considering the play or clearance at the exit opening thereof, the soldering wire will exit in a bent shape. This shape will be influenced to a large extent by the play or clearance. Therefore, it would be advantageous to provide a soldering apparatus capable of feeding a number of sizes of soldering wire and arranged so that the exiting soldering wire is not bent.
Another single-hand-soldering apparatus is disclosed in German DE-GM No. 82 25 325.0, having a tube shaped mouth piece which is movable relative to the soldering iron tip. The soldering wire is guided through the mouth piece towards the soldering iron tip. This tube shaped mouth piece is maintained by a spring in a position which prevents premature melting of the soldering wire. It would be advantageous, however, to provide a soldering apparatus in which the soldering wire would not contact the soldering area until after the soldering iron tip has heated the soldering area and which does not bend the soldering wire at the pivot axis of the mouth piece structure.
In addition, it would further be advantageous to provide a soldering apparatus in which the structure of the tube adjacent the soldering iron tip prevents blocking and incrustation of the passage through the tube.